Electrical Properties and Piezoresistance Effects of Evaporated Lead Telluride Thin Films

Abstract

In order to realize the Johnson U BV and Kron-Cousins RI photometric systems in BFOSC, glass filters were purchased according to the Bessell prescription. All the filters are anti-reflection coated on both sides to increase the transmission. By comparing two dome flat-field exposures taken through any one of these filters set in two orientations 90 • apart, inhomogeneities in the filter transmission is clearly demonstrated. Using a PDS microphotometer, we have confirmed that the form of their spectral transmission curve varied from point to point on the filters. This kind of inhomogeneity cannot be eliminated by dividing by flat-fielding exposure and must be ascribed to inhomogeneities in the coating. This is not some accidental defect in coating, it is in the existing coating technique because all the filters (including the narrow-band interference ones) for the BFOSC and a Hβ filter made by another manufacturer showed a similar pattern. We found that for the studies of variable stars with amplitudes less than 0.05 mag. or studies aiming at establishing accurate C-M diagrams of star clusters, the usual uncoated Schott glass filters of Bessell's prescription are to be preferred.

Photovoltaic properties of lead telluride thin film

“…The incident energy of the mercury light is 3.4 eV which generates N~ was estimated to be 1.1 x 1020 cm-3. This value corresponds to N d reported previously [4]. The depletion region extends to a distance 2 and can be estimated using the relation …”

“…Above 60 ~ the breaking of the lines is noticed and the activation energies of 0.038, 0.075 and 0.063 eV show P-type conduction due to generation of Pb vacancies in the lattice. The activation energy values in the present work have been reported previously [4].…”

“…PbTe thin film is a N-type conductor below substrate temperature of 270 ~ [4]. The substrate temperature in the present work is 200 ~ the carriers are electrons due to excess Pb atoms.…”

“…From an engineering point of view PbTe thin films are preferable for applications such as strain gauge, for large piezoresistance effect. Polycrystalline PbTe thin films are prepared on glass substrates by means of evaporation under various conditions of substrate temperature [4]. The transition of conduction type from N-type to P-type occurs in the vicinity of the substrate temperature of 270 ~ This paper reports measurements of I-V characteristic of illuminated thin film and piezoresistance effect.…”

Sequential Organic−Inorganic Templating and Thermoelectric Properties of High-Aspect-Ratio Single-Crystal Lead Telluride Nanorods

“…Recently devised sonochemical and autoclavebased techniques, [21][22][23] e.g., <10 nm diameter nanorods 12 with aspect ratios j7, and formation of single-crystal nanowires through nanoparticle coalescence and ripening, however, are promising approaches. 31 Here, we report a completely new two-step organicinorganic templating method to obtain single-crystal PbTe nanorods with aspect ratios up to 27, at moderate temperatures, without using an autoclave. We exploit anisotropic nanotube growth through organic surfactant templating and transform the nanotubes into single-crystal PbTe nanorods via reaction with a lead salt obviating any subsequent template removal.…”